Improvement in metal-drilling machines



D. W. POND. Metal-Drilling Machine 10.204,248.'

Patented Maygzs, 187s.

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NJERS. FHOTU-LITHOGRAPHEH, WASHINGTON. D. C.

UNITED STATEsPATENT OFFICE.

DAVID W. POND, OF WORCESTER, MASSACHUSETTS.

IMPROVEMENT IN METL-'DRILLING MACHINES.

Specication forming part of Letters Patent No. 204,248, dated May 28,1878; application filed 'May 10, 1878.

To all whom it may concern:

Be it known that I, DAVID W. POND, of Worcester, in the county ofWorcester and State of Massachusetts, have invented certain new' anduseful Improvements in Upright Drilling-Machines; and I declare thefollowing to be a description of my said invention, sufficiently Dill,clear, and exact to enable others, skilled in the art to which itappertains to make and use the same, reference being had to theaccompanying drawings, which form a part of this specification, and inWhich- Y Figure 1 represents a side view of such parts of an uprightdrilling-machine as are necessary to illustrate the nature of myinvention; and Fig. 2 represents a plan view of the same.

This invention relates to the construction of the devices forcounterbalancing the drillspindle and sliding head in uprightdrillingmachines, the same being an improvement in the mechanismdescribed in Letters Patent N o. 150,890; and my invention consists inthe peculiar arrangement of the balancing-lever and manner of combiningthe same with the sliding head and drill-spindle quill, as hereinafterdescribed.

In the drawings, A denotes the main supporting-frame, with guideways A'.B is the sliding head-block, movable on the ways A'. O is thedrill-spindle,y D, the feed-quill, with rack D', and E the feed pinionand its shaft, all of which parts may be constructed and arranged in theordinary manner, as may also the operating-gears, driving-pulleys, andother portions of the machine not shown in the drawings.

F indicates the counter-balance attachment lever, to which the cord orchain-G' of the counter-weight G is connected adjustably or otherwise,as preferred. Said lever F I arrange in a central position in rear ofthe drillspindle O, and attach its forward end directly to the upper endof theAfeed-quill D, in the present instance by pivoting the end of thelever between ears d, formed on the top end of the rack D', which isrigidly attached to or forms a part oi' said quill, as shown.

The rear end of lever F, which extends through a suitable opening, b, atthe upper part of the head-casting B, is connected by the link I to thelower central rear part B' of the sliding head B by a pivot-joint, i, asindicated, the lever F, link l, and their connecting-joints d e t', allbeing arranged centrally of the machine, or so as to operate in a planecoincident with the vertical aXis of the drillspindle, sliding head, andsupporting-frame.

The link I is inclosed within the casting or interior of the -head B,the opening b being made of a size sufficient for the free working ofthe parts, as required. vBy constructing and arranging the parts asAherein shown and described, the force of the counter-balance weight iscaused to act centrally on the mechanism. The strain at the forward endof the lever F being brought into direct line from the joint d to thefeed-4 pinion E produces no side strain or twisting action on the quillD, While the link I, being attached at the lower rear part of the headB, causes the strain of the counter-weight to act in opposition to theleverage of the head, since its tendency is to draw vthe heel or lowercorner B'away from the guides A', thus overcoming the tendency of thehead to cramp on the guides by its' own weight, and greatly reducing thefriction of the parts by avoidance of side strains or cramping action.

It will be understood that I do not make claim herein, broadly, to alever device for connecting the balanced parts with the chain of thecounter-weight in such manner that both spindle and head can becounterbalanced by a single weight; but

What I claim as my' invention, and desire to secure by Letters Patent,is-

1. The combination, with the drilling-spindle and sliding head in anupright drillingmachine, of a connter-balance-weight mechanism,substantially such as described, arranged centrally in rear of thedrill-spindle, and connected by pivot or hinge attachment directly tothe upper end of the feed-rack or quill and linked to the lower rearpart of the headblock, for'the purposes set forth.

2. In combination, substantially as herein shown and described, thefeed-quill and rack D D', provided with ears d, the sliding head D.1878;

VDAVID W. POND.

Witnesses CHAs. H. BURLEIGH, AUG. BUEHLER.

Witness my hand this 8th day of May, LA.

